I'm not sure about the iD tech 4 engine. We'll have to wait for quite a while, and it'll be loads more work. That's not a problem per se, but at the moment, for us, iD tech 3 is enough. We might have a look at iD tech 4 when the time comes. I'm uncertain as to what you're referring to as the 'fun parts', which iD tech 3 shouldn't be able to reproduce. Please explain.
If you have a better forum suggestion, feel free to share
Edit: actually, seeing if we can get a forum at lucasforums might be an idea. Although I don't know who to ask..